/*
 * Copyright (c) 1999, 2000
 * Intel Corporation.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * 3. All advertising materials mentioning features or use of this software must
 *    display the following acknowledgement:
 * 
 *    This product includes software developed by Intel Corporation and its
 *    contributors.
 * 
 * 4. Neither the name of Intel Corporation or its contributors may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL INTEL CORPORATION OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */

/*++

Module Name:

    writev.c
    
Abstract:

    Functions implementing the standard "writev" system call interface


Revision History

--*/


#ifdef foo
#include <efi_interface.h>
#include <unistd.h>
#include <fcntl.h>
#define KERNEL
#include <errno.h>
#undef KERNEL
#include "./filedesc.h"

#include <libc_debug.h>
#include <assert.h>
#endif

#include <stdlib.h>
#include <unistd.h>
#include <sys/uio.h>
#include <string.h>
#ifndef KERNEL
#define KERNEL
#include <errno.h>
#undef KERNEL
#else
#include <errno.h>
#endif

//
//  Name:
//      writev
//
//  Description:
//      BSD writev interface for libc
//
//  Arguments:
//      File Descriptor (index into file descriptor table)
//      iovec pointer
//      size of iovec array
//
//  Returns:
//      number of bytes written
//

ssize_t
writev( 
    int fd, 
    const struct iovec *iov, 
    int iovcnt
    )
{
	const struct iovec	*pVecTmp;
	char			*pBuf, *pBufTmp;
	size_t			TotalBytes, i, ret;

	//
	//  See how much memory we'll need
	//

	for (i = 0, TotalBytes = 0, pVecTmp = iov; i < (size_t)iovcnt; i++, pVecTmp++) {
		TotalBytes += pVecTmp->iov_len;
	}

	//
	//  Allocate a contiguous buffer
	//

	pBuf = (char*)malloc (TotalBytes);
	if (pBuf == NULL) {
		errno = ENOMEM;
		return -1;
	}

	//
	//  Copy vectors to the buffer
	//

	for (pBufTmp = pBuf; iovcnt; iovcnt--) {
		bcopy(iov->iov_base, pBuf, iov->iov_len);
		pBuf += iov->iov_len;
		iov++;
	}

	//
	//  Use standard write(2) then free buffer
	//

	ret = write (fd, pBuf, TotalBytes);
	free (pBuf);

	return (ret);
}
